function strrev(string) {
  //       discuss at: http://phpjs.org/functions/strrev/
  //      original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
  //      bugfixed by: Onno Marsman
  // reimplemented by: Brett Zamir (http://brett-zamir.me)
  //        example 1: strrev('Kevin van Zonneveld');
  //        returns 1: 'dlevennoZ nav niveK'
  //        example 2: strrev('a\u0301haB') === 'Baha\u0301'; // combining
  //        returns 2: true
  //        example 3: strrev('A\uD87E\uDC04Z') === 'Z\uD87E\uDC04A'; // surrogates
  //        returns 3: true

  string = string + '';

  // Performance will be enhanced with the next two lines of code commented
  //      out if you don't care about combining characters
  // Keep Unicode combining characters together with the character preceding
  //      them and which they are modifying (as in PHP 6)
  // See http://unicode.org/reports/tr44/#Property_Table (Me+Mn)
  // We also add the low surrogate range at the beginning here so it will be
  //      maintained with its preceding high surrogate
  var grapheme_extend =
    /(.)([\uDC00-\uDFFF\u0300-\u036F\u0483-\u0489\u0591-\u05BD\u05BF\u05C1\u05C2\u05C4\u05C5\u05C7\u0610-\u061A\u064B-\u065E\u0670\u06D6-\u06DC\u06DE-\u06E4\u06E7\u06E8\u06EA-\u06ED\u0711\u0730-\u074A\u07A6-\u07B0\u07EB-\u07F3\u0901-\u0903\u093C\u093E-\u094D\u0951-\u0954\u0962\u0963\u0981-\u0983\u09BC\u09BE-\u09C4\u09C7\u09C8\u09CB-\u09CD\u09D7\u09E2\u09E3\u0A01-\u0A03\u0A3C\u0A3E-\u0A42\u0A47\u0A48\u0A4B-\u0A4D\u0A51\u0A70\u0A71\u0A75\u0A81-\u0A83\u0ABC\u0ABE-\u0AC5\u0AC7-\u0AC9\u0ACB-\u0ACD\u0AE2\u0AE3\u0B01-\u0B03\u0B3C\u0B3E-\u0B44\u0B47\u0B48\u0B4B-\u0B4D\u0B56\u0B57\u0B62\u0B63\u0B82\u0BBE-\u0BC2\u0BC6-\u0BC8\u0BCA-\u0BCD\u0BD7\u0C01-\u0C03\u0C3E-\u0C44\u0C46-\u0C48\u0C4A-\u0C4D\u0C55\u0C56\u0C62\u0C63\u0C82\u0C83\u0CBC\u0CBE-\u0CC4\u0CC6-\u0CC8\u0CCA-\u0CCD\u0CD5\u0CD6\u0CE2\u0CE3\u0D02\u0D03\u0D3E-\u0D44\u0D46-\u0D48\u0D4A-\u0D4D\u0D57\u0D62\u0D63\u0D82\u0D83\u0DCA\u0DCF-\u0DD4\u0DD6\u0DD8-\u0DDF\u0DF2\u0DF3\u0E31\u0E34-\u0E3A\u0E47-\u0E4E\u0EB1\u0EB4-\u0EB9\u0EBB\u0EBC\u0EC8-\u0ECD\u0F18\u0F19\u0F35\u0F37\u0F39\u0F3E\u0F3F\u0F71-\u0F84\u0F86\u0F87\u0F90-\u0F97\u0F99-\u0FBC\u0FC6\u102B-\u103E\u1056-\u1059\u105E-\u1060\u1062-\u1064\u1067-\u106D\u1071-\u1074\u1082-\u108D\u108F\u135F\u1712-\u1714\u1732-\u1734\u1752\u1753\u1772\u1773\u17B6-\u17D3\u17DD\u180B-\u180D\u18A9\u1920-\u192B\u1930-\u193B\u19B0-\u19C0\u19C8\u19C9\u1A17-\u1A1B\u1B00-\u1B04\u1B34-\u1B44\u1B6B-\u1B73\u1B80-\u1B82\u1BA1-\u1BAA\u1C24-\u1C37\u1DC0-\u1DE6\u1DFE\u1DFF\u20D0-\u20F0\u2DE0-\u2DFF\u302A-\u302F\u3099\u309A\uA66F-\uA672\uA67C\uA67D\uA802\uA806\uA80B\uA823-\uA827\uA880\uA881\uA8B4-\uA8C4\uA926-\uA92D\uA947-\uA953\uAA29-\uAA36\uAA43\uAA4C\uAA4D\uFB1E\uFE00-\uFE0F\uFE20-\uFE26]+)/g;
  // Temporarily reverse
  string = string.replace(grapheme_extend, '$2$1');
  return string.split('')
    .reverse()
    .join('');
}